JP2005208599A - Water-repellent acoustic material and interior material for vehicle using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acoustic material having superior water repellency and sound absorptivity, and an interior material for vehicle which uses the same. <P>SOLUTION: At least two layers which are a layer of nonwoven fabric consisting of polyester fiber and organic fiber, such as polyester fiber and aramid fiber, and a layer of a skin material, such as paper and nonwoven fabric, whose air permeable quantity measured based on JIS L 1096 is 0.01 to 30 cc/cm<SP>2</SP>/sec and which is processed with a fluorine-based or silicone-based water repellent are laminated. Then a surface layer material is laminated on this sound absorber, to obtain the interior material for vehicle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a water-repellent sound-absorbing material used in fields such as air conditioners, electric refrigerators, electric appliances, automobiles, and building wall materials, and particularly used in vehicles having noise sources such as automobiles, trains, and aircraft. . The present invention also relates to a vehicle interior material using the water-repellent sound absorbing material.

  Engines and drive systems mounted on vehicles and the like generate noise when driven. In order to prevent this noise from causing discomfort to the occupant, sound absorbing materials are often attached in layers on the walls of engine hoods, dash panels, noise covers, cab floors and other wall materials as a noise countermeasure. . The sound-absorbing material used here is exposed to water or oil such as gasoline or light oil and becomes contaminated. If this water or oil penetrates into the sound-absorbing material and becomes dirty, the subsequent handleability and recyclability deteriorate.

For this reason, a sound absorbing material having water repellency and oil repellency has been proposed. For example, in Patent Document 1, a bulk density of 0.05 g / cm ³ to 0.00 is formed of resin fibers having a fiber diameter of 15 μm to 25 μm. There has been proposed a sound-absorbing material characterized in that the surface of a 2 g / cm ³ non-woven fabric has been subjected to water / oil repellent treatment (Japanese Patent Application Laid-Open No. 8-76768). However, this sound-absorbing material cannot completely prevent water intrusion or engine oil or light oil penetration due to high-pressure car washing during vehicle inspections and periodic inspections.

  Further, in Patent Document 2 (Japanese Patent Laid-Open No. 2000-81888), in a sound absorbing material in which a sound absorbing member and a synthetic resin nonwoven fabric are laminated, a synthetic resin film layer is disposed between the sound absorbing member and the synthetic resin nonwoven fabric, and synthesized. The resin nonwoven fabric has been subjected to water and oil repellency treatments, and a sound absorbing material has been proposed in which small holes are perforated on the entire surface of the synthetic resin film layer. However, the operation of perforating small holes on the entire surface of the synthetic resin film and disposing it between the sound absorbing member and the nonwoven fabric complicates the manufacturing process and leads to an increase in cost.

Patent Document 3 (Japanese Patent Application Laid-Open No. 2002-287767) contains rock wool, glass fiber, organic fiber that does not melt under molding conditions and fibrous binder as essential fibers, and these are irregularly oriented in a mixed state, In addition, a mat-like sound-absorbing material in which fibers are bonded with a fibrous binder and a skin material made of a polyester fiber-based non-woven fabric treated with water, oil, and flame retardant are integrally coated and molded. A sound absorbing material for a vehicle is disclosed. However, rock wool and glass fibers tingle when they are touched during work, which hinders workability. In particular, glass fibers have a drawback that they are damaged or scattered during work and transportation.
Japanese Patent Laid-Open No. 8-76768 JP 2000-81888 A JP 2002-287767 A

  Accordingly, it is an object of the present invention to provide a sound absorbing material that is excellent in sound absorbing performance and water repellency, and a vehicle interior material using the same.

  As a result of diligent research to solve the above-mentioned problems, the present inventors have laminated a non-woven fabric layer made of organic fibers with a water-repellent skin material treated with a water-repellent material to reduce water permeability and sound absorption. The present inventors have found that a sound-absorbing material excellent in the above can be obtained, and reached the present invention.

That is, the present invention has a non-woven fabric made of organic fibers and an air flow rate measured based on JIS L 1096 of 0.01 to 30 cc / cm ² / sec, and at least two skin materials treated with a water repellent. Provided is a water-repellent sound-absorbing material characterized in that layers are laminated.

  In the sound-absorbing material of the present invention, the organic fiber is preferably a polyester fiber that is excellent in the texture and formability of the nonwoven fabric and can be easily recycled. Nonwoven fabrics made of polyester fibers and aramid fibers are also preferred because of their excellent heat resistance and flame retardancy.

  Moreover, it is preferable that the said skin material is paper or a nonwoven fabric, and when an aramid paper is used for a skin material, the sound-absorbing material excellent in the flame retardance is obtained. Recycling is easy when the organic fibers constituting the nonwoven fabric and the skin material are composed of the same kind of synthetic fibers.

  In the sound absorbing material of the present invention, a film having air permeability may be further laminated. By laminating such a breathable film, it is possible to prevent water from entering while maintaining the air flow rate.

  Furthermore, the present invention provides an interior material for a vehicle characterized in that at least a surface layer material is laminated on the skin material side of the water-repellent sound absorbing material described above.

  As described above, according to the present invention, it is possible to provide a sound-absorbing material having excellent sound absorption performance and excellent water repellency at low cost. In addition, according to the present invention, it is possible to provide a vehicle interior material that is excellent in sound absorption performance and water repellency, and also excellent in recyclability.

  The water-repellent sound-absorbing material of the present invention is formed by laminating at least two layers of a nonwoven fabric layer made of organic fibers and a skin material. The organic fibers constituting the nonwoven fabric are one or more of synthetic fibers, chemical fibers such as rayon, natural fibers such as cotton, hemp, jute, wool, and anti-hairs (recovered and recycled fibers). Can be used. Of these, synthetic fibers are preferred from the viewpoint of durability. Examples of such fibers include thermoplastic fibers such as polyester fibers, polyamide fibers, acrylic fibers, polypropylene fibers, and polyethylene fibers. The fiber material is produced according to a known method such as wet spinning, dry spinning, or melt spinning. Can be used. Among these, polyester fiber, polypropylene fiber, and polyamide fiber are preferable from the viewpoint of excellent durability and wear resistance, and these fibers can be used alone or in admixture at any ratio. In particular, polyester fibers are most preferable because the raw material polyester can be easily recycled by heat melting of the waste nonwoven fabric, is excellent in economy, has a good texture of the nonwoven fabric, and is excellent in moldability. Some or all of these thermoplastic fibers may be bristles. Miscellaneous felts can also be used as the organic fiber nonwoven fabric.

  Said polyester fiber means the polyester fiber which consists of dicarboxylic acid which uses ethylene terephthalate as the main repeating unit, and glycol, and a biodegradable polyester fiber. Examples of the biodegradable polyester fiber include polycaprolactone, polyethylene succinate, polybutylene succinate, polyethylene adipate, polybutyrea dipate, polyethylene succinate / adipate copolymer, polylactic acid, and other dicarboxylic acids based on these and / or Or the polyester fiber etc. which copolymerized glycol are mentioned. Examples of the dicarboxylic acid component include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, and the like. Examples of the glycol component include ethylene glycol, propylene glycol, tetramethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol and the like. A part of the dicarboxylic acid component may be replaced with adipic acid, sebacic acid, dimer acid, sulfonic acid metal-substituted isophthalic acid, etc., and a part of the glycol component may be diethylene glycol, neopentyl glycol, 1, 4-cyclohexanediol, 1,4-cyclohexanedimethanol, polyalkylene glycol, and the like may be substituted. This polyester includes various inorganic particles such as titanium oxide, silicon oxide, calcium carbonate, silicon nitride, clay, talc, kaolin, and zirconium acid, and particles such as crosslinked polymer particles and various metal particles. Antioxidants, sequestering agents, ion exchangers, anti-coloring agents, waxes, silicone oils, various surfactants and the like may be added.

  The fiber length and fineness of the thermoplastic fiber are not particularly limited, but the fiber length is preferably 10 mm or more. Filaments or staples may be used, but in the case of staples, the fiber length is preferably 10 to 100 mm, and particularly preferably 20 to 80 mm. By using short fibers having a fiber length of 10 mm or more, the tangled short fibers are less likely to fall off the nonwoven fabric. On the other hand, when the fiber length is long, the card passing property tends to be inferior. A fineness of 0.5 to 30 dtex, particularly 1.0 to 10 dtex is preferably used.

  The said thermoplastic short fiber can be used individually or in mixture of 2 or more types, respectively. It is also possible to use a mixture of thermoplastic short fibers of the same or different types and different in fineness and fiber length. In this case, the mixing ratio of the fibers is arbitrary, and can be appropriately determined according to the use and purpose of the nonwoven fabric.

  In order to obtain a sound-absorbing material excellent in heat resistance or flame retardancy, it is preferable to use a nonwoven fabric using heat-resistant fibers together with thermoplastic fibers, particularly polyester fibers. Specific examples of the heat resistant fiber include, for example, aramid fiber, polyphenylene sulfide fiber, polybenzoxazole fiber, polybenzthiazole fiber, polybenzimidazole fiber, polyether ether ketone fiber, polyarylate fiber, polyimide fiber, fluorine fiber, and flame resistance. One type or two or more types of organic fibers selected from modified fibers can be mentioned. As these fibers, any conventionally known fibers, those manufactured according to a known method or a method analogous thereto can be used. Here, the flame-resistant fiber is mainly produced by baking acrylic fiber at 200 to 500 ° C. in an active atmosphere such as air, and is a precursor of carbon fiber. For example, the product name “Lastan” manufactured by Asahi Kasei Co., Ltd., the product name “Pyromex” manufactured by Toho Tenax Co., Ltd., and the like can be mentioned.

  Among the above heat resistant fibers, at least one organic selected from aramid fibers, polyphenylene sulfide fibers, polybenzoxazole fibers, polyether ether ketone fibers, polyarylate fibers and flame resistant fibers from the viewpoint of low shrinkage and processability. Fiber is preferable, and aramid fiber is particularly preferable.

  The aramid fibers include para-aramid fibers and meta-aramid fibers. Para-aramid fibers are particularly preferable from the viewpoint of less heat shrinkage. Examples of para-aramid fibers include polyparaphenylene terephthalamide fibers (US DuPont, manufactured by Toray DuPont, trade name “KEVLAR” (registered trademark)), copolyparaphenylene-3,4′-oxydi. Commercial products such as phenylene terephthalamide fiber (manufactured by Teijin Limited, trade name “Technola” (registered trademark)) can be used.

  When both the heat-resistant fiber and the thermoplastic fiber are constituent fibers of a nonwoven fabric, short fibers are preferable from the viewpoint of mixing properties. The fiber length and fineness of the heat-resistant short fiber are not particularly limited, and can be appropriately determined depending on the compatibility with the thermoplastic fiber and the use of the sound absorbing material. The fineness is preferably 0.5 to 30 dtex, particularly preferably 1.0 to 10 dtex. The fiber length is not particularly limited, but it is preferably a short fiber having a fiber length of 20 to 100 mm, particularly 40 to 80 mm in consideration of productivity.

  The heat resistant fibers can be used alone or in admixture of two or more. It is also possible to mix and use fibers of the same kind or different kinds and different in fineness and fiber length. In this case, the mixing ratio of the fibers is arbitrary and can be appropriately determined according to the use and purpose of the sound absorbing material.

  The thermoplastic fiber and heat-resistant fiber constituting the nonwoven fabric are preferably blended at a ratio of (thermoplastic short fiber / heat-resistant short fiber) = 95/5 to 55/45 (mass ratio). When the ratio exceeds 95/5, the flame retardancy of the nonwoven fabric becomes insufficient, and liquid dripping (drip) tends to occur. That is, by containing 5% by mass or more of heat-resistant fiber in the web and entangled with the thermoplastic fiber, the thermoplastic fiber can be prevented from burning and melting. On the other hand, when the ratio is less than 55/45, the flame retardancy is good, but when the nonwoven fabric is processed into a desired size, it becomes difficult to cut, resulting in poor workability and poor economic efficiency. From the viewpoint of flame retardancy and processability, the ratio (mass ratio) of thermoplastic short fibers / heat resistant short fibers is more preferably 88/12 to 65/35, and still more preferably 85/15 to 65/35. It is desirable.

  In the present invention, in order to improve the abrasion resistance and sound absorption characteristics of the nonwoven fabric, it is preferable to contain fine denier thermoplastic short fibers in the thermoplastic fibers. Examples of the fine denier thermoplastic fiber include one or more fibers selected from the aforementioned polyester fiber, polypropylene fiber, polyethylene fiber, linear low density polyethylene fiber, ethylene-vinyl acetate copolymer fiber, and the like. Can do.

  The fineness of the fine denier thermoplastic fiber is usually 0.0001 to 5.0 dtex, preferably 0.5 to 6.6 dtex, and particularly preferably 1.1 to 3.3 dtex. If the fineness is too thin, the processability is deteriorated, and if it is too thick, the sound absorption characteristics are deteriorated. The fiber length is not particularly limited and can be appropriately determined depending on the compatibility with the heat-resistant fiber and the use of the flame-retardant nonwoven fabric. Usually, the short fiber is preferably 10 to 100 mm, particularly 20 to 80 mm. .

  When blending fine denier fibers in the web, if the amount is too small, the blending effect cannot be obtained. If the amount is too large, the flame retardancy of the nonwoven fabric may be impaired. Preferably it is 30-60 mass%.

In this invention, the fabric weight of a nonwoven fabric is 150-800 g / m < ² >. If the basis weight is too small, the shape retention of the web layer will be poor, and if the basis weight is too large, the energy required for entanglement of the fibers will increase, or the entanglement will be insufficient, resulting in inconveniences such as deformation during the production of the nonwoven fabric.

  The web can be manufactured according to a conventional web forming method using a conventional web forming apparatus. For example, the blended thermoplastic short fibers and heat-resistant short fibers are opened using a card machine and then formed on a web.

  The nonwoven fabric preferably used in the present invention is an integral body obtained by interlacing a thermoplastic short fiber or a fiber web obtained by mixing a thermoplastic fiber and a heat-resistant short fiber by a needle punch or a water jet punch by a conventional method. However, a needle punch is preferable. By performing the punching treatment, the web fibers can be entangled to improve the abrasion resistance of the nonwoven fabric.

  After needle punching and water jet punching, the nonwoven fabric can be obtained by drying in the same manner as in the prior art and heat setting as necessary.

When the short fiber nonwoven fabric is too small in bulk, the heat insulating property, sound absorbing property and flame retardancy are lowered, and if it is too large, the wear resistance, workability and flame retardancy are lowered. It needs to be in the range of 2 g / cm ³ . Preferably 0.01 to 0.1 g / cm ^3, more preferably 0.02 to 0.08 g / cm ^3, still more preferably in the range of 0.02~0.05g / cm ^3.

  In the present invention, the thicker the nonwoven fabric, the better the sound absorption. However, from the viewpoints of economy, ease of handling, space securing as a sound absorbing material, etc., preferably 2 to 100 mm, more preferably 3 to 50 mm, still more preferably. Is 5 to 30 mm.

The water-repellent sound-absorbing material of the present invention has at least two skin layers treated with a water-repellent agent having an air permeability of 0.01 to 30 cc / cm ² / sec measured according to the above-mentioned nonwoven fabric and JIS L 1096. Layers are stacked. The air flow rate measured based on JIS L-1096 is 0.01 to 30 cc / cm ² / sec, preferably 0.05 to 20 cc / cm ² / sec. If the air flow rate is less than 0.01 cc / cm ² / sec, the permeability of gas such as engine gas is low, and if it exceeds 30 cc / cm ² / sec, the sound absorption performance is lowered and the water repellency is affected.

  The form of the skin material may be various forms such as paper, film, non-woven fabric (dry and wet), woven fabric, knitted fabric, etc., but paper and non-woven fabric are preferred from the viewpoint of having low air permeability.

  When the skin material is paper, it may be ordinary paper such as western paper or Japanese paper whose material is a cellulosic material, or may be so-called synthetic paper such as polyester paper produced by making synthetic fibers.

  In the case of a nonwoven fabric, the constituent fibers may be either staples or filaments. From the viewpoint of production cost and strength characteristics, a nonwoven fabric composed of long fibers is also preferably used. In particular, a thermal bond fabric method in which fibers are partially bonded to each other by a spun bond method is preferable in terms of sound absorption. As such a non-woven fabric, a commercially available non-woven fabric, for example, a trade name Acter (manufactured by Toray Industries, Inc.) can be used as it is. In addition, wet nonwoven fabrics made of short fibers, such as paper or felt made from chopped fibers, pulp or staples, are also preferably used. Among these, when the non-woven fabric is made of polyester fibers and aramid fibers, use of aramid paper as a laminated skin material can provide a sound absorbing material excellent in sound absorption and water repellency, and excellent in heat resistance and flame retardancy. it can.

  In the present invention, the fibers constituting the skin material have a fineness of 0.01 to 10 dtex, preferably 0.01 to 3 dtex.

The skin material may contain ultrafine fibers having a fineness of 0.5 dtex or less generated from the split fibers. The skin material using such ultrafine fibers can easily have an air permeability of 0.01 to ³⁰ cm ³ / cm ² / sec. Here, as the split fibers, those produced by a conventionally known method can be used. For example, the split fibers can be divided into ultrafine fibers having a fineness of 0.5 dtex or less divided by a fluid flow such as a water flow or an external force such as a needle, or a solvent. Ultrafine fibers having a fineness of 0.5 dtex or less obtained by dissolving and removing the resin component can be used. The skin material containing such ultrafine fibers is preferably made of a needle punched nonwoven fabric or a fluid flow entangled nonwoven fabric. Above all, after forming a fiber web using split fibers, a fluid stream (especially a water stream) is jetted onto the fiber web to split the split fibers to generate ultrafine fibers and to entangle the fibers. Most preferred is a non-woven fabric.

The thickness of the skin material before the water repellent treatment is arbitrary, but is preferably 0.01 to 2 mm, more preferably about 0.05 to 1 mm. The weight of the skin material is preferably light, but from the viewpoint of strength, it is preferably 20 to 400 g / m ² , more preferably about 50 to 300 g / m ² .

  Although the raw material of a skin material is not specifically limited, It is preferable that it is comprised with the same raw material as the said nonwoven fabric. That is, for example, a large amount of sound absorbing material used as a vehicle interior material such as an automobile is required and can be recycled. Therefore, if a material different from the non-woven fabric layer is used, it becomes necessary to disassemble and difficult to recycle. For example, in the case of a nonwoven fabric containing a polypropylene material, a skin material made of polypropylene is used. A combination of a non-woven fabric containing a polyester material and a polyester spunbonded non-woven fabric, for example, the trade name Acter (manufactured by Toray Industries, Inc.) is preferably used.

（式中、Ｒ_１、Ｒ_２、Ｒ_３、Ｒ_４は互いに同一または異なっていてもよく、水素もしくは、炭素数が１〜４のアルキル基であり、ｎは２〜１０である）
で表されるアルコキシシランを含有するコーティング液も撥水剤として用いることができ、このコーティング液は表皮材に塗布または含浸したのち、加熱するとポリシロキサン構造を主構造とする高分子膜を形成し、撥水性能を奏する。 As the water repellent, known water and oil repellents such as a fluorine-based resin and a silicone-based resin can be used. In addition, the following general formula (1)

(In the formula, R ₁ , R ₂ , R ₃ and R ₄ may be the same or different from each other, and are hydrogen or an alkyl group having 1 to 4 carbon atoms, and n is 2 to 10).
A coating solution containing an alkoxysilane represented by the following formula can also be used as a water repellent, and after coating or impregnating the coating material, the coating solution forms a polymer film having a polysiloxane structure as the main structure when heated. Has water repellency.

  The coating liquid contains a compound represented by the general formula (1) as a main component, and is disclosed in JP-A Nos. 2002-1873 and 2002-321327. Examples of the compound represented by the general formula (1) include methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, Examples include condensates of various silane monomers such as butyltriethoxysilane, methyltripropoxysilane, ethyltripropoxysilane, propyltripropoxysilane, and butyltripropoxysilane. The compound represented by the general formula (1) may be a condensate obtained by condensing two or more of the above monomers. Monomers or two or more monomers may be added to the coating solution, or a condensate may be added.

  In this coating liquid, usually, as a catalyst for curing and solidifying the compound represented by the general formula (1), for example, acid catalyst such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, ammonia, tetramethylammonium hydroxide, ethanolamine A normal catalyst such as a base catalyst is allowed to coexist with water. In addition, hydrolyzable organometallic compounds, such as compounds containing titanium, zircon, aluminum or tin, also have a catalytic action and react with moisture in the skin material or moisture in the air to hydrolyze. It combines with the compound represented by 1) to form a network structure and form a polymer film. More specific examples of such organometallic compounds include tetrapropoxy titanate, tetrabutoxy titanate, tetrapropoxy zirconate, tetrabutoxy zirconate, tripropoxy aluminate, aluminum acetylacetonate, dibutyltin diacetate, dibutyltin dilaurate, etc. can do.

  In addition, an organic solvent such as alcohols such as methanol, ethanol and isopropanol, glycols such as ethylene glycol, propylene glycol and diethylene glycol, and cellosolves such as methoxyethanol and butoxyethanol are added to the coating liquid.

（式中、Ｒ_５、Ｒ_６およびＲ_７はそれぞれ同一または異なり、水素、アルキル基またはアルケニル基であり、Ｒ_８はその分子内にエポキシ基またはグリシジル基を含んでいてもよいアルキル基、アルケニル基またはフェニル基である。ｍは１〜１０を示す）
で表される化合物を添加することができる。 Further, the coating liquid contains a smaller amount of the following general formula (2) than the compound represented by the general formula (1), which is the main component.

(Wherein R ₅ , R ₆ and R ₇ are the same or different and each represents hydrogen, an alkyl group or an alkenyl group, and R ₈ represents an alkyl group, alkenyl which may contain an epoxy group or glycidyl group in the molecule) Group or phenyl group, m represents 1 to 10)
The compound represented by these can be added.

  Examples of the compound represented by the general formula (2) include vinyltrimethoxysilane, phenyltrimethoxysilane, γ- (methacryloxypropyl) trimethoxysilane, γ-glycidoxypropyltrimethoxysilane, aminopropyltri Methoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, etc., and about 2 to 10 of these The condensate of can be illustrated. The compound represented by the general formula (2) may be two or more of the above monomers, or may be a condensation of two or more of the monomers.

  A known water / oil repellent such as silicone oil may be added to each of the coating liquids.

  The skin material coated or impregnated with the coating solution is heated at, for example, 300 ° C. or less, preferably 80 to 150 ° C. for about 2 minutes to 1 hour, thereby forming a polymer film having a polysiloxane structure as a main structure on the surface. Is done.

  Moreover, the sound-absorbing material of the present invention may be laminated with a film having air permeability in addition to the skin material and the nonwoven fabric. The film having air permeability is disposed on the skin material, between the skin material and the nonwoven fabric, or below the nonwoven fabric. Examples of the air permeable film include a synthetic resin film and a film in which small holes are perforated on the entire surface of the synthetic resin film. By laminating a breathable film, it is preferably used in that it can prevent water from entering while maintaining the air flow rate, and can easily control the air flow rate by adjusting the size of the holes.

The laminate of the skin material and the nonwoven fabric may be in a non-adhesive state, but preferably bonded by a normal bonding method, such as fusion, stitching, needle punching, adhesive bonding, thermal embossing, ultrasonic Bonding, lamination by general methods such as adhesion, sintering adhesion by adhesive resin, adhesion by thermal adhesive sheet, adhesion by welder, etc. are used. Thermal fusion using a hot-melt adhesive powder and a hot-melt nonwoven fabric is preferable because it can be laminated without impairing air permeability and sound absorption performance.

  Moreover, the water-repellent sound-absorbing material of the present invention may be colored with a dye or a pigment as necessary. As a coloring method, an original yarn obtained by spinning a dye or pigment mixed with a polymer before spinning may be used, or fibers colored by various methods may be used. The sound absorbing material may be colored with a dye or a pigment.

  In addition, the water-repellent sound-absorbing material of the present invention includes an acrylic resin emulsion, a phosphate ester-based flame retardant, a halogen-based flame retardant, water, and the like, as necessary, in order to further improve the flame retardancy and wear resistance. An acrylic resin emulsion or an acrylic resin solution containing a known flame retardant such as a Japanese metal compound may be coated or impregnated.

  The water-repellent sound-absorbing material of the present invention can be preferably applied to a vehicle interior material by laminating a surface layer material thereon. The surface layer material is laminated on the skin material side of the water-repellent sound-absorbing material so as not to impair the water repellency and sound-absorbing properties of the water-repellent sound-absorbing material. When a surface material is laminated on the skin material, the surface material may be laminated directly on the skin material, or may be laminated via another layer (for example, a gray layer).

  As the surface layer material, a surface layer material usually used for a vehicle interior material can be used. For example, a nonwoven fabric, a woven fabric, a moquette, a tricot, a jersey, a carpet, leather, artificial leather, a synthetic resin sheet, etc. are illustrated. Among these surface layer materials, a nonwoven fabric is preferable because of its excellent recyclability and low cost. The nonwoven fabric preferably used is obtained by entanglement and integration of a fiber web obtained by mixing short fibers by a needle punch or a water jet punch by a conventional method, and a needle punch is preferable. Short fibers are practically colored with dyes or pigments.

  The short fiber is preferably a synthetic fiber similar to the non-woven fabric constituting the water-repellent sound-absorbing material. Among these, a polyester fiber (including biodegradable polyester fiber), a polypropylene fiber, and a polyamide fiber are preferable. Or can be mixed and used in an arbitrary ratio. In particular, polyester fiber (including biodegradable polyester fiber) can be easily recycled and reused by heat melting of waste non-woven fabric, because it is economical, has good non-woven texture, and has excellent moldability. Is most preferred. Some or all of these fibers may be bristles.

  Lamination of the skin material and the surface layer material is bonded by a normal bonding method. For example, fusion, stitching, needle punching, adhesive bonding, heat embossing, ultrasonic bonding, sinter bonding with adhesive resin, bonding with thermal adhesive sheet, bonding by general methods such as welding with welder, laminated Is used.

  The water-repellent sound-absorbing material of the present invention can be used for various uses by applying a known method or the like according to the purpose or use thereof and processing it into an appropriate size or shape. The sound-absorbing material of the present invention can be used for all applications where water repellency and sound-absorbing properties are required. For example, the sound-absorbing material is suitable for automobiles, freight cars, aircrafts, etc. Can be used for In particular, automotive ceiling materials, floor materials, option mats, rear packages, door trims; insulators in dashboards of automobiles, trains, aircraft, etc .; electrical appliances such as refrigerators, vacuum cleaners, air conditioners; speaker diaphragms; lawn mowers, It can be used for various applications such as electric tools such as electric drills and electric excavators.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited only to a following example. In addition, the measuring method of each characteristic value in the following examples and comparative examples is as follows.

[Air flow rate]
It measured based on the fragile method of JIS L-1096. The skin material was measured in a state before being bonded to the nonwoven fabric or the surface layer material. However, for the water-repellent processed after bonding, the skin material was peeled off and measured.

[Sound absorption rate]
Using an automatic normal incidence sound absorption rate measuring device (manufactured by Denki Sokki Co., Ltd.), the sample was attached with the skin portion facing the sound source.

[Water repellent performance]
It measured according to the shower method and A method (low water pressure method) of JIS L-1092.

(Example 1)
Para-aramid fiber “Kevlar (registered trademark)” staples (1.7 dtex × 51 mm) manufactured by Toray DuPont Co., Ltd. and polyester staples (1.7 dtex × 51 mm) manufactured by Toray Industries, Inc. are mixed at a weight ratio of 30:70. A Kevlar mixed nonwoven fabric having a thickness of 10 mm and a basis weight of 400 g / m ² was prepared by a needle punch method (bulk height: 0.04 g / cm ³ ).

On the other hand, a para-aramid fiber “Kevlar (registered trademark)” 3 mm chopped fiber yarn manufactured by Toray DuPont Co., Ltd. is used as the skin material and calendered to obtain a Kevlar paper with a thickness of 95 μm and a basis weight of 72 g / m ^2. It was. The obtained Kevlar paper was immersed in a 20 g / liter solution of a water repellent finishing agent (Asahi Guard GS-10, manufactured by Meisei Chemical Industry Co., Ltd.) and squeezed with a rubber roller mangle (squeezing pressure 2 kg / cm ² , speed 4 m). / min.). The wet pickup amount of the water repellent was 520 g / m ² . Immediately, it was dried in a heating furnace (120 ° C. × 2 minutes), and then cured in a heating furnace (170 ° C. × 1 minute).

An ethylene-vinyl acetate copolymer powder (manufactured by Tokyo Ink Co., Ltd., 2030-M) is applied (10 g / m ² ) to the surface of the water repellent treated Kevlar paper prepared in this manner, and Kevlar is applied to this surface. The mixed non-woven fabrics were superposed and bonded together in a heating furnace (135 ° C. × 1 minute) to prepare a water-repellent sound absorbing material.

The performance of the water-repellent sound-absorbing material thus prepared was such that the normal incident sound absorption coefficient was 89% (2000 Hz), the air flow rate was 0.92 cc / cm ² / sec, and the water repellency was grade 5.

(Example 2)
The same water repellent finish as in Example 1 was applied by hand spray to the paper side of the laminate obtained by bonding Kevlar paper and Kevlar mixed nonwoven fabric in the same manner as in Example 1 (wet pickup amount of water repellent solution) 320 g / m ² ). Immediately, drying and curing were simultaneously performed in a heating furnace (150 ° C. × 5 minutes).

The water-repellent sound-absorbing material prepared in this way has sufficiently maintained the adhesive strength of the bonding surface, and as performance, the normal incident sound absorption coefficient is 82% (2000 Hz), and the air flow rate is 0.90 cc / cm ² / sec. The water repellency was grade 5.

(Example 3)
In place of the water-repellent finishing agent used in Example 1, a coating liquid (SPK-312C, manufactured by Kouichi Co., Ltd.) containing an alkoxysilane was processed as a skin material. In the same manner as in Example 1, it was bonded to a nonwoven fabric to obtain a water repellent sound absorbing material. This sound absorbing material had a normal incident sound absorption coefficient of 94% (2000 Hz), an air flow rate of 0.77 cc / cm ² / sec, and a water repellency of 5th grade.

(Comparative Example 1)
In Example 1, a sound absorbing material was prepared in the same manner as in Example 1 except that Kevlar paper was not processed with a water repellent. The sound absorbing material obtained had a sound absorption rate of 83% (2000 Hz), an air flow rate of 1.21 cc / cm ² / sec, and a water repellency of first grade.

Example 4
Instead of the skin material used in Example 1, a polyester spunbonded nonwoven fabric (manufactured by Toray Industries, Inc., trade name: ACSTER G2260-1S, thickness: 620 μm, basis weight: 260 g / m ² ) is used as a coating liquid containing alkoxysilane (( Co., Ltd., Kouichi, SPK-312C) was processed (attachment rate 2.6%) to obtain a skin material. In the same manner as in Example 1, it was bonded to a nonwoven fabric to obtain a water repellent sound absorbing material.

The water-repellent sound absorbing material thus prepared had a normal incident sound absorption coefficient of 83% (2000 Hz) and an air flow rate of 8.3 cc / cm ² / sec. The water repellency was grade 4 (shower method) and 435 mmH ₂ O (low water pressure method).

(Example 5)
A nonwoven fabric having a thickness of 2.5 mm and a basis weight of 100 g / m ² was prepared by repeating the same operation as in Example 1 except that the web was prepared only from the polyester fiber (1.7 dtex × 51 mm) (bulk height: 0.04 g / cm ³ ).

An ethylene-vinyl acetate copolymer powder (manufactured by Tokyo Ink Co., Ltd., 2030-M) was applied (10 g / m ² ) to the surface of the same skin material used in Example 4, and this surface was applied. Polyester nonwoven fabrics were stacked and bonded together in a heating furnace (135 ° C. × 1 minute) to prepare a water-repellent sound absorbing material. As for the performance of the water-repellent sound absorbing material thus prepared, the normal incident sound absorption coefficient was 90% (2000 Hz).

(Example 6)
Polyester staples manufactured by Toray Industries, Inc. (1.7 dtex × 44 mm), polyester staples manufactured by the same company (6.6 dtex × 51 mm) and low-melting yarn “Safmet” (4.4 dtex × 51 mm) are mixed at a mass ratio of 60:20:20. Fibers were entangled by a needle punch method and then heat treated at 150 ° C. for 3 minutes to obtain a nonwoven fabric having a thickness of 10 mm, a basis weight of 400 g / m ² and a bulk density of 0.04 g / cm ³ .

On the other hand, as a skin material, a polyester spunbonded nonwoven fabric (manufactured by Toray Industries, Inc., trade name ACSTER G2150-1SBKO, thickness 450 μm, basis weight 150 g / m ² ), a coating solution containing alkoxysilane (manufactured by Kouichi Co., Ltd.) SPK-312C) was processed (attachment rate 2.8%) to obtain a skin material. In the same manner as in Example 1, it was bonded to a nonwoven fabric to obtain a water repellent sound absorbing material.

The water-repellent sound absorbing material thus prepared had a normal incident sound absorption coefficient of 86% (2000 Hz) and an air permeability of 26.3 cc / cm ² / sec. The water repellency was grade 4 (shower method) and 390 mmH ₂ O (low water pressure method).

(Example 7)
A nonwoven fabric having a thickness of 2.5 mm and a basis weight of 100 g / m ² was prepared by repeating the same operation as in Example 1 except that the web was prepared only from the polyester fiber (1.7 dtex × 51 mm) (bulk height: 0.04 g / cm ³ ).

An ethylene-vinyl acetate copolymer powder (manufactured by Tokyo Ink Co., Ltd., 2030-M) was applied (10 g / m ² ) to the surface of the same skin material used in Example 4, and this surface was applied. A polyester film was overlaid, an ethylene-vinyl acetate copolymer powder was further applied, a polyester non-woven fabric was overlaid and bonded together in a heating furnace (135 ° C. × 1 minute) to prepare a water-repellent sound-absorbing material. As for the performance of the water-repellent sound absorbing material thus prepared, the normal incident sound absorption coefficient was 90% (2000 Hz).

(Example 8)
When an interior material was prepared by laminating a 3 mm thick polyester fiber needle punch carpet (weight per unit area: 250 g / m ² ) on the surface of the water repellent sound absorbing material prepared in Example 4, the sound absorbing property was excellent. An interior material was obtained. Further, since the sound-absorbing material has a high water pressure resistance, the sound-absorbing property was maintained for a long time without water penetrating through the surface layer material.

Claims (10)

A non-woven fabric made of organic fibers and an air permeability measured based on JIS L 1096 are 0.01 to 30 cc / cm ² / sec, and at least two layers of a skin material treated with a water repellent are laminated. A water-repellent sound-absorbing material characterized by that. The water-repellent sound-absorbing material according to claim 1, wherein the organic fiber is a polyester fiber. The water-repellent sound-absorbing material according to claim 1, wherein the organic fibers are polyester fibers and aramid fibers. The water repellent sound-absorbing material according to any one of claims 1 to 3, wherein the skin material is paper. The water repellent material according to claim 4, wherein the paper is aramid paper. The water repellent material according to any one of claims 1 to 3, wherein the skin material is a non-woven fabric. The water-repellent sound-absorbing material according to any one of claims 1 to 6, wherein the organic fibers constituting the nonwoven fabric and the skin material are composed of the same type of synthetic fibers. The water-repellent sound-absorbing material according to any one of claims 1 to 7, wherein the water-repellent agent is a coating liquid containing an alkoxysilane represented by the following general formula (1).

(In the formula, R ₁ , R ₂ , R ₃ and R ₄ may be the same or different from each other, and are hydrogen or an alkyl group having 1 to 4 carbon atoms, and n is 2 to 10). The water-repellent sound-absorbing material according to any one of claims 1 to 8, wherein a film having air permeability is further laminated. An interior material for a vehicle, wherein at least a surface layer material is laminated on the skin material side of the water-repellent sound-absorbing material according to any one of claims 1 to 9.